Color yielding photographic elements



Sept. 6, 1949. o. w. MURRAY 2,481,475

COLOR YIELDING PHOTOGRAPHIG ELEMENTS Filed March 2, 1945 HARDENED HYDROPHILIC COLOR FORMER FILM HARDENED HYDROPHILIC COLOR FORMER LAYER Wlllfllfilm TRANSPARENT suppom HARDENED uvonopmuc COLOR FORMER LAYER CLEAR COLLOID LAYER COLLO|D-$ILVER HALIDE LAYER I. E El I TRANSPARENT SUPPORT HARDENED HYDROPHILIC COLOR FORMER LAYER 'IIIIIIIIIIII .IIIIIA TRANSPARENT SUPPORT F 1 E 4 COLLOID-S|LVER HALIDE LAYER HARDENED HYDROPHILIC COLOR FORMER LAYER TRANSPARENT-SUPPORT COLLOID SILVER HALIDE LAYER +COLOR FORMER 'IIIIIIIIIIIIIIIIII COLLOID LAYER FOR IMBIBITION IMAGE HARDENED HYDROPHILIC COLOR FORMER LAYER EAR COLLOID LAYER OID SILVER HALIDE LAYER TRANSPARENT SUPPORT ENED HYDROPHILIC. COLOR FORMER LAYER ATTOR/Vfy Patented Sept. 6, 1949 COLOR YIELDING PHOTOGRAPHIC ELEMENTS Otis Willard Murray, Fords, N. J assignor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware Application March 2, 1945, Serial No. 580,561.

3 Claims.

This invention pertains to photography. More particularly, it pertains to improved color yielding elements for the recording of photographic colored images which have 'at least one stratum composed of a hardened hydrophilic synthetic color former. It also relates to processes of making such elements.

An object of this invention is to provide new materials for use in color photography. A further object is to provide improved elements for recording photographic images in color. A more specific object is to provide improved color yielding elements useful in the procedures of United States Patent 2,328,034. Still another object is to provide strong, stable, flexible, light-insensitive color yielding elements which are capable of forming quinoneimine or azomethine dyes.

The above objects may be accomplished by the invention hereinafter described and illustrated in the accompanying drawing.

The novel color-yielding elements of this invention have at least one stratum composed of a hardened hydrophilic synthetic color former. These colors formers are hydrophilic synthetic colloids having as a part of their chemical structure color former nuclei which have been hardened by reaction with a protein hardening agent. Such nuclei or color former components have, as the active coupling groups, a structure which may be represented by the general formula where X is an HO radical or an RI-IN radical, where R is hydrogen, an alkyl or substituted alkyl group, e. g., methyl, ethyl, betachlorethyl, betahydroxyethyl, benzl, etc., and n is or 1. Thus X may be a primary or secondary amine group. Such active coupling groups are found in reactive methylene dye intermediates and in aromatic hydroxyl and amino compounds and include reactive ethenol, aminoethenyl, 4-hydroxyand 4- amino-1,3-butadienyl groups. These groups are found in phenols, naphthols, anilines, naphthylamines, acylacetamides, cyanoacetamides, betaketoesters, pyrazolones, N-homophthylamines, coumaranones, indoxyls, thioindoxyls, etc.

The hydrophilic synthetic colloid color formers can be hardened prior to being cast into layers or films or after formation by reaction with a protein hardening agent. Suitable agents include aldehydes and ketones and aldehyde-yielding materials, such as formaldehyde, acetaldehyde, glyoxal, acrolein, methylol ureas, e. g., methylolurea and dimethylolurea. The amount of hardening agent per part of color former can be varied over a fairly Wide range, e. g., 0.5+1.0 part per part of color former. The hardening treatment should be carried out to such an extent that a layer 15 microns in thickness will not show any solubility in a 5% solution of NazCOa at 68 F. in 5 minutes.

Various types of' color yielding elements embodying the novel strata are comprehended by the invention. One practical type consists of a film or foil composed solely of the hardened hydrophilic colloid color former which is of suflicient thickness to permit handling by the technician without rupture or disintegration. A thickness of at least 5 to 10 microns. is generally necessary for adequate film strength but thicknesses of 3 to microns represents a practical range.

Another type consists of a support which may be composed of paper, metal, cellulose derivatives, high polymers, e. g., nylon, etc., which has imposed thereon at least one layer composed solely of a hardened color former.

Still another type consists of a support which may be composed of paper, metal, cellulose derivatives, high polymers, e. g., nylon, etc., which has imposed thereon at least one layer composed solely of a hardened hydrophilic color former, and at least one light-sensitive silver salt layer; the hardened hydrophilic color former layers being outer-most and physically separated by a stratum which prevents color coupling coaction with any silver salt layer of the element. In some instances the stratum may be a water impermeable membrane or a film base. In others it may be somewhat water-permeable but of such thickness that color coupling cannot take place through the stratum.

The supports for certain of the elements of this invention may be transparent and quite thin so long as they posses sufficient mechanical strength for processing and handling, or they may be adhesively joined to a paper or transparent support of greater strength and/or thickness or to a thin transparent membrane or support.

In the accompanying drawing which forms a part of this specification there are shown several representative types of color yielding elements.

Fig. 1 is an enlarged cross-sectional view of a color yielding element comprising a film composed of a hardened hydrophilic color former.

.Fig. 2 is an enlarged cross-sectional view of another color-yielding element comprising a support and a layer of a hardened hydrophilic color former.

Fig. 3 is an enlarged cross-sectional view of another element comprising a, support, a colloid silver halide layer, a clear colloid layer, and a layer of a hardened hydrophilic color former.

Fig. 4 is an enlarged cross-sectional view of another element comprising a support, a colloid silver halide layer on one side thereof'and 'a layer of a hardened hydrophilic color former on the other side;

Fig. 5 is an enlarged cross-sectional view of an element similar to that of Fig. 4; wherein the silver halide layer contains a color former.

Fig. 6 is an enlarged cross-sectional view of an element similar to that of Fig. 3. which contains" a gelatin-commi'nuted silver layer on the support and a hardened hydrophilic color former layer 'on the other side of. the support. g I

Fig. 7 is an enlarged cross-sectional view of an halide layer and a clear gelatin layer on one side thereof a colloid color --layer on the other side.

The above figures will be further explained in the following examples.

Erample I A solution was prepared by admixing 25 grams of salicyaldehydeeortho-sialfob'enzaldehyd' polyvinyl acetalwi-th 5 cc. of-5N NaOH and 500 cc. of water. To this was added 5. grams of dimethylolurea and 50 cc. of water. The resulting solution was heated toe80. C; for 30 minutes. It was cast onto a polished'inetal support: in the formof a thin film and allowed to. dry. The resulting film was stripped from the support and was found to be insoluble in water and alkaline photographic developer solutions..' It had a structure like that illustrated in Fig. 1 of the drawing.

A color separation negativewas printed .onto a positive film bearing a geliatinos-s-ilver halide layer and the film was. developed and fixed using standard solutions. The positivesilver images were then bleached in an aqueous-solution of potassium ferricyanide to a silver ferroc'yah ide images and the film was then washed thoroughly and soaked in- 10% sodium carbonate. The color yielding film element descri-bed' i "-the preceding paragraph was soaked a. solution of the following composition: l

element comprising a support, a colloid silver- The two films were pressed tog-ether; and held in I intimatecontact untila, blue-green; color d-ma tormed in the: latter element. andthey were then separated. The resulting element can thenv be mounted on a support with, similar elements, preparedfrom different color separation positives and similar elements yielding d-ifiererrt colors, e. g., magenta and yellowwhich are mountedon each other inregister to. form a. three-colonpioture as described in United States Patent 2,328,034. 1

'the'n coated onto a cellulose aoetate fiim base to form -anelement of the type shown in Fig. aw-of the drawing.

The element can be used for the formation of the blue-green color of three-color prints after the manner disclosed in Example I of United States Patent 2,328,034.

Instead of coating the filmonto a permanent support, it can be cast as described in Example I hereer'; or the elemer-it cail be used; as'the base element on'whieh two il iflerent colored image bearing elements free from supports can be mounted in register.

Example III A solution was prepared by mixing 10 grams of the poiyvinyi actal of N(m-formylphenyl)- l-acet Xy-Z-naphthalenesulfonamide, 2 cc. of 5N NaOH, 40 cc. of ethanol and 160 cc. of water. To the solutionwere added's grams of dimethylolurea'and 25 cc. of water.

The resulting solution was cast onto a paper support forming an element of the typeshown in Fig. 2 of the drawing. Upon color c'oupling yellow color yielding-layer or stratum..

7 Example V A color yielding element ofthe. type shown in Fig. 3 was prepared by coating a gl'atino-silver halide emulsion l'ayer on'to a -cellulose a'cetate film base having: a gelatin-phenol. substratmn. on the iatterjiayer was coated the sorutionjdescribed in Example I toidrin an outer hardencid color forlm-ng, polyvinyl ac'etai" ctomr former. Iayer.

The silver halide. layeristhen expose by printing a color. separation negative onto it and developed in an ordinary positive type. metolhydroquinonedeveloper and washed. The outer layer is then converted into. a colored image bearing layer by imbibition. contact development with a bleached color separation positive prepared from *another color separation negative; The inner layer is then developed in a color coupling developer solution containirrgJLNs'dietHyIamh'Q- aniline "and anorange-red color :rorm'er consisting of a,- mixture or: pnenvimerhaiey a o d acetoacetaniline in a 45 4 ratio andhaving the following-composition?- 1 a i-phenyi-3-inerhy1pyra2oii ne-5; grams r0 Acetdacetanil-ide 4.--..- do 1 8 Diethylpaiiaph enyle'nedialm L., doh I 3 NazCOs ..do 30 H2,o 1 v liter 1 The silver and silver sattsare; then removed by means of; Farmer's. reducer-,xwashed and dried:v

V In Murray wilted-States-application-Serial; No. 500,198-filed August 2*], 1 943;;now' abandoned, there are described several azltemativezwaysiofi'deyelopr ing elements: similar to. the multilayer elements described above." The present elelnehta'difieir only' in having a: hydrophilie color former layer instead of-anomehandeiied' layerf andzcamlie processed: to colordpicizlitesiby aimf thfilflms cedures 'glescrihedinsaid;application...

- The color yielding elements may contain lightsensitive layers composed of simple or mixed silver halides which may contain the usual sensitizers, desensitizers, stabilizers, fog inhibitors, emulsion hardeners, etc. Suitable types include silver chloride, silver bromide, silver chlorobromide, silver chloride-bromide-iodide, silver bromide-iodide, etc., which may contain cyanine, cyazine, merocyanine, styryl and related sensitizing dyes. The silver halide layers are anchored to the supports by means ofthe usual subbing solutions. Such solutions are also useful for anchoring dye component layers to bases.

While the above description has been restricted for the most part to the formation of dye images in non-photographic layers by bringing a separate element containing reducible silver salt images into contact with the dye yielding layer in the presence of the constituents of a color coupling' developer, it is also possible to form such dye images in separate elements containin images other than silver salt images.

The dye components or color formers are in general selected so that they together form. a composite dye image Whichreproduces a color scene or object. Thus the dye components used in the layer which is treated by contact development in general should form dyes complementary in color to that which exposed the color separation negative record employed therewith. Likewise, the dye components or color formers used in the inner layer or the developing solution used for processing thereof should form a dye which is complementary in color to that which exposed the color separation record. When reproduction of an original color object field is not a desideratum, a dye which forms any desired color can be used.

As examples of suitable orange-red color formers which can be used in emulsion layers or in developing solutions upon being dispersed therein if necessary by means of alkali and/or alcohol are the diacylacetamino-1,2,4,5-benzobisthiazoles of United States Patent 2,140,540 of which difuroylacetamino-1,2,4,5-benzobisthiazole and diacetoacetamino 1,2,4,5 benzobisthiazole are especially useful. Additional yellow color formers include 2 hydroxy 3 naphthoylam'inobenzoylacetanilide, sodium stearoylaminobenzoylacetanilide-p-carboxylate, furoylacet-p-amino phenylamyl ether (described in U. S. Patent 2,184,303) and dipicolinoylacetbenzidine.

Suitable non-migratory magenta color formers which are especially useful are 1-(3'-sulfophenyl) -3 (4 stearoylamino phenyl) -3-(4"- dodecoylamino-phenyl) 5 pyrazolone, 4,4'-bis- (3-methyl pyrazolonyl-l) -diphenyl (described in U. S. Patent 2,200,924), 4,4'methylene-bis- (m stearoylaminophenyl) methyl pyrazolone (described in U. S. Patent 2,294,909) and 4,4-osulfobenzylidene-bis-(phenyl methyl pyrazolone) (described in U. S. Patent 2,294,909).

Suitable non-migratory blue-green color formers of especial utility include 4,4-di-(1-hydroxy-2-naphthoyl-amino) diphenyl, l-hydroxy- 2-carboxy 5 dodecoylamino naphthalene, l-N- stearoyl-4-N-(1'-oxy-2'-naphthoyl) phenylenediamine sodium sulfonate, resorcinol mono-ndodecyl ether (described in U. S. Patent 2,166,181) product of p-hydroxy-benzoic acid and formaldehyde (described in U. S. Patent 2,323,481), product of polyvinyl alcohol and salicyl-aldehyde (described in U. S. Patent 2,310,943).

In the multilayer elements described in Figs. 6 and 7 the colloid-silver halide layers are selectively sensitized to difierent regions of the spectrumand'the color formers are chosen so that they form dyes complementary in color to the utilized sensitivity of the silver halide layers. Thus for blue, green and red sensitive layers there should be used color formers which form yellow, magenta and blue-green dyes respectively. These elements are similar to those described in U. S. Patent 2,369,171 but utilize hardened hydrophilic color formers.

Additional color formers which are useful not only with arylene diamino developing agents, but also the aryl hydrazines are described in U. S. Patents 2,154,918, 2,166,181, 2,178,612, 2,179,228, 2,179,238, 2,179,239, 2,213,986, 2,179,244, 2,186,045, 2,186,719, 2,186,734, 2,186,735, 2,186,736, 2,186,849, 2,140,540, 2,133,937, and 2,200,924.

The preferred developing agents which may be used in the dye coupling development steps hereof are derivatives of p-phenylenediamine and particularly the asymmetric dialkyl p-phenylenediamines of 1 to 4 carbon atoms, e. g., p-aminodimethyl aniline, p aminodiethylaniline, p aminodibutylaniline, etc. 0 t h e r developing agents which may be used include p-phenylene diamine itself, p-methylaminoaniline, p-ethylaminoaniline, p-aminophenol, N,N diethyl o phenylenediamine, chloro-p-phenylenediamine, 1,2,5-to1uylenediamine, 2 amino 5 diethylamino-toluene, p amino-N-phenylmorpholine, N-p-aminophenyl-piperidine, N methyl-N-hydroxyethyl-p-phenylenediamine, N butyl-N-hydroxyethyl-p-phenylenediamine, 2-amino-5-(N- butyl-N-hydroxyethyl) aminotoluene, beta-gamma-dihydroxy-propyl-p phenylenediamine, etc.

These aromatic amino developing agents in the form of their organic or inorganic acid salts may be used in the preparation of the developing solutions. The salts are in general more stablethan the free bases. As examples of suitable salts, mention is made of the hydrochlorides, sulfates, acetates, etc.

In place of the particular hydrophilic color formers described in the working examples, there are many others which can be hardened in like manner. Thus any of the specific polyvinylacetal color formers described in U. S. Patent 2,310,943, the acetals of hydroxyl polymers described in U. S. Patent 2,320,422 and the condensation products of phenols and naphthols or hydroxy aromatic carboxylic or sulfonic acids with difunctional resin-forming reagents such as aldehydes and ketones, etc. described in U. S. Patent 2,323,481 can be hardened and cast into layers in like manner. Still other hydrophilic color formers which can be similarly hardened are described in U. S. Patents 2,178,612, 2,186,734, 2,307,399 and in application Serial No. 528,943, filed March 31, 1944, now U. S. Patent 2,397,865.

A number of different bleaching procedures can be used for the elements which are used for contact development. Films or plates containing a positive or negative silver image can be bleached to redevelopable silver salts, as for example with potassium ferricyanide, copper chloride, or copper bromide in the presence of an oXidiZing agent such as chromic acid, potassium ferricyanide in the presence of alkali carbonate or ammonia, etc.

In place of the sodium carbonate solutions may be used potassium carbonate, potassium hydroxide, lithium carbonate, and other aqueous solutions for soaking the bleached photographic elements. The concentrations may range somewhat depending on the pH of the particular agent, the bleaching agent used, the dye intermediate used and the concentration of the developing What is claimed is:

1. A photographic element comprising a sup port in sheet form bearing an outermost lightinsensitive layer composed of a polyvinyl acetal color former containing an active dye coupling structure of the formula 1 where n is a number taken from the class consisting of 0 and 1 which color former has been hardened by treatment with a protein hardening agent taken from the class consisting of aldehydes, ketones, and aldehyde yielding compounds, and at least one light-sensitive colloid silver halide emulsion layer separated from said color where viiis a number taken freinthe class consisting of 0 and 1 wl'iich'olor Iormer has been hardened by treatment with a protein hardening agent taken from the class consisting of aldehydes, ketones and aldehyde yielding compounds. 3. A photographicelement comprising a trans parent water-impermeable film base, a lightsensiti ie' colloid silver halide emulsion layer-on one surface of said base and on the other surface crsaid base a light-insensitive layer composed of I a polyvinyl acetal color former containing an active dye coupiing'struetur' of the formula where n is a number taken from the class consisting of 0 and 1 which color former has been hardened by treatment with a methylolurea. o'rrs WILLARD MURRAY,

I nnr'anenoas CITED 'l he following references'are of record in the me or patent; I Y I ED STATE s PATENT I 5 Number V 3 'Name' 7 Date" 2,169,250 Izard Aug. 15, 1939 2,211,323 Fordyce e Aug. 13, 1940 21245213 Murray et al. 'J1.me 10, 1941 2,253,078 Lowe Aug. 19,1941 $279,411 Peterson Apr; 14, 1-942 2,282,001 Russell-ct a l. May 5,1942 2,310,943 Dorough et a1. '4 Feb. 16; 1943 2,320,422 Fro'hlicli a f June 1, 1943 FOREIGN PATENTS 7 I Number Country Date 503,752 Great Britain Apr. 11, 1939 I 537,256 a Great "Britain ...-.a' June 716, 1941 

